𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Formation of the CaiiK-line core with arbitrary temperature minima

✍ Scribed by Herbert A. Beebe


Publisher
Springer
Year
1971
Tongue
English
Weight
639 KB
Volume
17
Category
Article
ISSN
0038-0938

No coin nor oath required. For personal study only.

✦ Synopsis


The formation of the solar Call K-line core is studied under the assumption of a two component chromosphere for many atmosphere models, which are tested by comparing observed and calculated average intensity profiles at several places on the solar disk. Non-LTE-line profile calculations are made using model atoms of two and three bound levels while the value and depth of the temperature minimum and turbulent velocity gradient are varied. A critique of several broad types of models is provided.

Limb darkening of the entire core, a K1 radiation temperature of 4300K and increasing limbward separation of the K2 peaks are predicted by a combination of a 'cool' component, covering 90 % of the solar disk, and a 'hot' component, representing the bright calcium network. The optimum cool component is characterized by a 4200K temperature minimum and low (~ 1 km/sec) microturbulent velocities. The hot component begins its outward temperature rise in the photosphere at 4300K and is never more than 500K hotter than the cool component.